This invention relates to automated apparatus for handling like circular articles, such as discs, rings, and lids, for example. More particularly, the present invention is directed to such an apparatus that is capable of receiving a multiplicity of such articles in a known or unknown orientation and processing them into a counted stack of articles, all having the same known orientation, ready for further manual or automated handling.
In order to remain competitive, many companies seek to simplify various aspects of their manufacturing processes through automation. This is particularly true of companies involved in bulk manufacturing, such as injection molding and printing, in which each step of a process may yield a number of circular articles that are generally flat in cross section. Often, the rate at which such articles can be produced is limited only by how fast they can be removed, collected or dispersed. In view of this challenge, automators have concentrated on fewer, more reliable process steps.
Previous automated processes for orienting articles such as lids have employed various techniques with differing degrees of success. The early prior art for handling lids or other articles used a simple accept/reject technique, in which improperly oriented articles were returned to a holding area proximate the input of the handling apparatus in the hope that the improperly oriented articles would become correctly oriented as the result of being randomly disturbed and processed again. In a high speed production process, this technique impedes the throughput and adds unecessary process steps.
Another prior art orientation technique employs a constant airflow sufficient to reorient incorrectly oriented articles, while not disturbing the correctly oriented articles. Obviously, the strength of an indiscriminate airflow is very important to ensure that only incorrectly oriented articles are reoriented. This process is also undesirable in the case of some flat articles that may be susceptible to being reoriented, regardless of whether they are properly or improperly initially oriented.
The more recent prior art processes involve more active control of the orientation of flat articles through the controlled use of airflow to orient the article based on a signal from a sensor capable of determining the present orientation of the article. These prior art systems are deficient in that they lack mechanical interaction with the flat article. By relying on the timing of a burst of air, these systems struggle to achieve the orientation accuracy required for later automation at the rates of current manufacturing and printing processes.
Prior attempts to create counted collections of generally flat articles have also proven to be inadequate. One such prior art technique involves the use of two horizontal bars positioned for rotation in the same direction to thereby impart a rotational force on the peripheral edge of the article so as to provide a stabilizing gyroscopic effect permitting the collection and maintenance of a rotating horizontal stack of the articles. The challenge associated with this technique is one of repositioning articles that are supplied in a generally horizontal position into a vertical position, taking into account the difference between the rotational speed of the article and that of the rotating bars. Prior art methods for repositioning flat articles from a horizontal position to a vertical position have either involved excessive floor space or complex mechanisms. Also, the physical and kinematic differences in the rotational speeds of the flat article relative to the rotating bars can result in erratic behavior of the article and lost production.
The foregoing deficiencies of prior art flat article orientation and collection techniques have prevented the successful counting of those articles, and have left the user to estimate the number of such articles in a stack, based upon the measured length of the stack. The impediments to accurate counting of collected flat articles are variations in their thickness, the inability to consistently closely pack the articles, and the invasive nature of apparatuses for separating a rotating collection thereof at the required length. These factors directly affect the length of a stack containing the required number of articles and frustrate automated or manual packing techniques for quickly determining the required number of articles, based upon a static measurement of stack length. Nevertheless, automated attempts at counting the number of flat articles in a stack are known in the prior art. One such apparatus involves the application of a lateral force along the length of the required number of articles to thereby separate them from articles that are subsequently collected. Another prior art counting apparatus attempts to insert a thin wheel into a seam between adjacent articles of a rotating stack thereof. Both of these prior art apparatuses cause disruption to the rotating stacks, oftentimes resulting in dropped articles that are lost to production.
Exemplary of prior art lid handling apparatus is that described in U.S. Pat. No. 3,682,292 to Drew.
The present invention is directed to an apparatus for receiving a multiplicity of like circular articles, such as discs, rings, and lids, for example, presented in a known or random horizontal orientation, and for collecting them into a horizontal counted stack in which each of the circular articles of the stack has the same on-edge or vertical orientation. In the embodiment of the invention in which the multiplicity of circular articles are presented in random horizontal orientation, some right side up and some upside down, they are sequentially conveyed to a pair of rotating spinner wheels that contact diametrically opposing points along the periphery of each of the circular articles to impart rotation thereto in a selected direction and, by means of a speed differential between the two spinner wheels, to propel each article into a rotating first article orientation tube. The direction of rotation of the rotating spinner wheels are a function of the initial sensed orientation, either right side up or upside down, of each of the circular articles. The combination of the downstream force imparted by the spinner wheels and the slight frictional engagement between the peripheral edge of each of the circular articles and the inner surface of the first article orientation tube serves to slow the speed at which each of the circular articles is spinning and to thereby reorient them into an on-edge or vertical position as they travel through the first orientation tube. An optional, shorter second article orientation tube is axially aligned with the first article orientation tube proximate the downstream end thereof and is rotationally driven in the same direction as that of the first article orientation tube and at a speed selected to promote discharge of the spinning, vertically-oriented circular articles from the downstream end thereof, where they are received in that position onto a pair of rotating spin bars. The rotating circular articles received on the pair of rotating spin bars are collected onto a counted horizontal stack of on-edge circular articles, at which time the stack is seperated from a subsequent collecting stack in preparation for manual or automatic removal from the rotating spin bars for further processing.
In a second embodiment of the present invention, one of the spinner wheels is eliminated, and the second article orientation tube is also eliminated. This configuration may be utilized in situations in which all of the circular articles are initially presented in a common horizontal orientation, either all right side up or all upside down.